1. Field of the Invention
The present invention relates generally to systems and methods for automatically filtering a cooking medium in a cooking apparatus, such as a fryer.
2. Description of Related Art
Known fryers, e.g., open-well fryers and pressure fryers, are used to cook various food products, e.g., poultry, fish, or potato products. Such fryers include a cooking vessel, e.g., a frypot, and the cooking vessel is filled with a cooking medium, e.g., an oil, a liquid shortening, or a meltable-solid shortening. Such fryers also include a heating element, e.g., an electrical heating element, such as a heating coil, or a gas heating element, such as a gas burner and gas conveying tubes, which heat the cooking medium in the cooking vessel. After the cooking medium reaches a preset cooking temperature, the food product is placed into the cooking medium, such that the food product is cooked in the cooking medium. For example, the food product may be positioned inside a product holder, e.g., a wire basket, and submerged in the cooking medium for a predetermined amount of time sufficient to cook or to complete the cooking of the food product. The amount of time sufficient to cook or to complete the cooking of the food product at a given cooking temperature depends on the type of food product which is cooked. Moreover, the cooking medium is used during several cooking cycles before the cooking medium inside the cooking vessel is filtered, replaced, or supplemented with a new or filtered supply of cooking medium.
Cooking medium may be filtered periodically to maintain cooking quality and to prolong the operational lifetime of the cooking medium. The filtering process removes cooking by-products, e.g., suspended food particles, ranging from dust-sized particles to larger pieces of crackling and small pieces of food product. Known contemporary filtering systems require the operator to manipulate valves to route the cooking medium through the filter and to return it to a cooking vessel, e.g., a frypot, disposed within the fryer. Even experienced operators may open or close the valves incorrectly, which increases operating expenses through lost time. Periodically, the drain pan under the fryer may be removed for cleaning or to discard the cooking medium. If the operator fails to replace the drain pan and opens the drain valve, the cooking medium drains out of the fryer and may be wasted, which greatly increases operating expenses. Moreover, it is generally desirable to filter the cooking medium for an appropriate time period. Consequently, if the filter time is too short, the cooking medium may not be not adequately filtered. If the filter time is too long, operating efficiency may be impaired, and cooking medium quality may be degraded unnecessarily by mechanical agitation and oxidation.
After filtering, the cooking medium may be returned to the frypot for further cooking. Known systems require an operator to operate a pump to refill the frypot with cooking medium. The amount of cooking medium in the frypot may vary based on the experience level of the operator, which may lead to inconsistencies in the quality of cooked food product. Moreover, such a refilling process requires the operator to supervise the refilling process, which reduces overall efficiency.
In addition, multiple frypots may be connected to a single drypan. Each frypot may be designated for cooking a different food product, e.g., chicken, french-fried potatoes, and fish. The flavor characteristics of each of these food products may become infused in the cooking medium. As a result, mixing cooking medium from frypots designated for different food products during filtering may adversely affect food quality, e.g., cooking chicken in a significant quantity of fish-flavored cooking medium may result in “fishy” chicken. Known filtering systems may permit an operator to simultaneously filter cooking medium for frypots designated for different food products, which may reduce the quality of cooked food product for the reasons noted above.
Referring to FIGS. 1 and 2, a fryer apparatus 10 comprising a known manual cooking medium filtering system and a known method for operating such a filtering system are depicted. Fryer apparatus 10 includes a frypot 16 having an open top 14 for receiving a food product. A cabinet 20, shown without a door for illustrative purposes, has brackets 32 supporting a drain pan 30 having a filter (not shown). Drain pan 30 includes a handle 34 that allows drain pan 30 to be removed from cabinet 20 for cleaning. Drain pan 30 is fluidly connected to frypot 16 via a drain hose 24 and a filter pipe 28. Disposed on filter pipe 28 is a filter pump 27 for drawing cooking medium to frypot 16 from pan 30. Frypot 16 includes a drain valve handle 22 that operates a drain valve (not shown) for selectively permitting cooking medium to drain from frypot 16 via hose 24. Frypot 16 also includes a filter valve handle 26 that operates a filter valve (not shown) for selectively permitting the introduction of cooking medium to frypot 16 from drain pan 30. Fryer apparatus 10 further may include a power supply 40 for powering filter pump 27, which may be actuated via a switch on control panel 18.
Referring to FIG. 2, a method for operating a known filtering system is depicted. To filter the cooking medium of fryer apparatus 10, the operator first ensures that the filter valve is closed 50. The operator turns drain valve handle 22 clockwise to manually open the drain valve 55, which uses gravity to permit the cooking medium to drain into drain pan 30. Next, the operator turns the filter valve handle 26 counter-clockwise to manually open the filter valve 60. The operator then turns drain valve handle 22 counter-clockwise to manually close the drain valve 55. The operator then actuates filter pump 70 using a switch that may be located on control panel 18. Next, the operator de-actuates the filter pump 75 to end the filtering process. Finally, the operator turns filter valve handle 26 in a clockwise direction to manually close the filter valve 80, so that operation of the fryer apparatus may resume.
Handles 22, 26 may be located in cabinet 20 beneath frypot 16. The above-described procedure is not intuitive unless the operator understands the logic and plumbing of the filter system, which generally is not the case for untrained operators. In known filtering systems, handles 22, 26 may be turned opposite directions to achieve the same result, in part because of design limitations within cabinet 20, which may add another element of complexity that may lead to operator error. Further, if one of the sequence of steps is omitted or executed out of order, then, at best, the operating efficiency of the fryer apparatus is impaired, and, at worst, the pump or frypot may be damaged. Even trained, experienced operators may omit or switch steps during peak cooking periods, e.g., the “lunch-rush.”